Chains consisting of a number of interconnected links and pins have a tendency to wear during normal use. Wear is retarded by hardening the contact surfaces of the links and pins which rub against one another during pivotal movement of the links about the pins. As the chain wears it elongates and when the hardened contact surfaces are worn away, the chain is sometimes subject to failure during use. A gauge is used for measuring chain wear as a regular part of a chain inspection to indicate when the chain is worn sufficiently to require repair or replacement.
Current gauges are capable of indicating when a chain is worn severely enough to warrant replacement but do not accurately indicate the service remaining before replacement is required. It is desirable to know the amount of chain wear so that the useful chain life remaining can be determined and subsequent servicing of the chain can be scheduled.
Chain wear gauges are not always simple to read or understand and sometimes calculations are required to determine the amount of wear. It is desirable to have a chain wear gauge which is easy to read and understand at a glance without tedious calculation.
Some gauges are only useful for measuring chain wear of chains having only one of several series of chain pitch thus requiring a different gauge for each series of chain pitch. It is desirable to have a single gauge for measuring chain wear for several series of chain pitch.